Device for controlling well flow



R. c. BAKER 2,644,527

DEVICE FOR CONTROLLING WELL FLOW 3 Sheets-Sheet l INVENTOR. QH/BENC19/4K5@ BY 'July 7,-'1953 Original Filed July 7. 1944 July 7, 1953 R.c. BAKER DEVICE FOR CONTROLLING WELL FLOW Original Filed July '7, 1944 5Sheets-Sheet 2 July 7, 1953 R. c. BAKER 2,644,527

. DEVICE FOR coNTRoLLlNG WELL Flow original Filed July 7, 1944 ssheets-sheet :5

.fipa/55N C A/a-re,

ATTORN EY.

Patented July 7, 1953 DEVICE FOR CONTROLLING WELL FLOW Reuben C. Baker,Coalinga, Calif., assignor to Baker Oil Tools, Inc., Vernon, Calif., acorporation of California.

Continuation of application Serial No.- 543,853,

July 7, 1944.

1950, Serial No. 147,631

15 Claims.

rI'his invention relates to well devices, and more particularly todevices for controlling the ilow of fluids from oil and gas Wells.

The present application is a continuation of my application for Devicesfor Controlling Well Flow, Serial No. 543,853, filed July 7, 1944, andnow abandoned. I

An object of the invention is to provide a device adapted for use inwell tubing and capable of automatically shutting off or greatlydiminishing the oW through the tubing upon decrease of the Well pressurebelow a predetermined value.

A further object of the invention is to provide a device adapted for usein well tubing which permits flow through the tubing to the surface ofthe well bore under normal pressure operating conditions, but whichautomatically shuts off or greatly restricts such flow upon drop inpressure below a predetermined value.

Still another object of the invention is to provide a device adapted foruse in well tubing in which the pressure of the fluid flowing throughthe tubing under normal operating conditions acts on pressure actuatablesurfaces of dissimilar areas to hold a flow control valve open againstthe action of a valve closing element. v

Upon decrease of the unit tubing pressure below a predetermined amount,the fluid acting on such surfaces of dissimilar areas is incapable ofholding the valve open against the force exerted by the valve closingelement.

Another object of the invention is to provide an automatic pressureresponsive shut oif valve device for controlling the iiow of iiuidthrough well tubing, which is capable of being reopened by applyingexternal uid pressure to the device.

Another object of the invention is to provide a valve device adapted foruse in Well tubing and which is held open by pressure acting on thedevice from above, and which will close upon decrease in such pressureto a predetermined degree.

Yet another object of the invention is to provide an improvedretrievable lockingv device forr anchoring flow control apparatus intubing previously installed in a well.

A further object of the invention is to provide an improved iiow controlapparatus adapted to be anchored in well tubing, which can be run intoand retrieved from the well tubing without substantially disturbing thedisposition of iiuid in rIlxis application February 23,

the tubing, and without removing the tubing fromk the well bore.

ln its general aspects, the invention contemplates the provision of avalve device which is controlled by fluid pressure acting on pressureactuatable surfaces of dissimilar areas. The pressure acts on a surfaceof greater area to exert a force tending to open the valve or hold it inopen position, and this pressure also acts on al pressure actuatablesurface of lesser area tending to move the valve toward closed position,or to a position in which flow through the valve is materiallyrestricted. This last-mentioned hydraulic valve closing force issupplemented by the force of a spring. There is, accordingly, a totalvalve opening force provided by the unit uid pressure acting on thepressure actuatable surface of greater area, and a total valve closingforce provided by the spring force plus the force of the unit fluidpressure acting on the fluid pressure actuatable surface of smallerarea. Eo long as the total force on the surface of larger area isgreater than the total force exerted by the spring and the fluid actingon the surface of smaller area, the valve will remain in open position;but as soon as the first-mentioned total force is less than the sum ofthe last-mentioned forces, the valve will move automatically to closedposition, or to a position in which flow through the tubing ismaterially decreased. This invention has other objects and aspects whichwill become apparent from a consideration of the several forms ofapparatus shown in the drawings accompanying and forming part of thepresent specification. These forms will now be described in detail, butit is to be understood that such detailed description is not to be takenin a limited sense, since the scope of the invention is best dened bythe claims appended hereto.

Referring to the drawings: l Figure lis an elevation of an apparatusshown installed in well production tubing; v Fig. 2v is a longitudinalsection through the, apparatus with its parts in retracted position forlowering through the production tubing;

Fig. 3 is a longitudinal section of part of the apparatus shown in Fig.2, in another operative position; Fig. 4 is a longitudinal sectionshowing the parts in position for elevating the apparatus through thetubing;

Fig. 5 is a longitudinal section showing the valve control portions ofthe apparatus in closed position;

Fig. 6 is a view similar to Fig. 5 of a modied form of apparatus; and

Fig. '1 is a View of the device disclosed in Fig. 6 in another operativeposition.

As disclosed in the drawings, the device consists of a lower ow controlportion A and an upper locking portion B for anchoring the device in awell tubing C previously installed in the bore hole.

The ow control portion includes a cylindrical body I having an adapteror cylinder head threaded into its upper end, and a tubular valve bodyI2 screwed into its lower end. The valve body has a plurality of lateralports I3 establishing communication between its interior and exterior,below which is carried a suitable packing to eiect a seal with thetubing wall; shown specifically as a packing cup I4, clamped between athimble I5 engaging a shoulder I6 on the valve body below the ports, anda clamp nut I1 threaded on the lower end of the valve body I2 andengaging the base portion of the packing cup I4. The clamp nut isprovided with a valve seat I8 adapted to be engaged by a valve head I9mounted on a valve stem 20 extending upwardly through the valve body I2and into the cylinder I0. A piston 2| is attached to the upper end ofthis stem 20 and carries a piston packing 22 secured to it by a suitablenut 23 threaded on the piston and engaging an annular V-shaped groove 24in the packing to force its outer lip 25 against the cylinder wall andits inner lip 26 against the piston, thus preventing leakage of iiuidpast the piston from above the packing 22.

The valve stem 20 may be considered as a small piston or piston rodwhose upper portion 21 extends into the cylindrical body or cylinder I0.Fluid through the valve body I2 is prevented from flowing or passingalong the small piston portion 21 into the cylinder I0 by a rod packing28, whose base portion engages the underside of a shoulder 29 extendinginwardly from the cylinder, and whose inner and outer lip portions 30,3| are forced against the piston or piston rod portion 21 and wall ofthe cylinder I9 by the clamping action of the end I2a of the valve bodyI2 screwed into the lower end of the cylinder. It will, accordingly, beseen that the rod packing 28 prevents fluid from below from passing intothe cylinder space 32 between the large piston 2| and the shoulder 29,and that the piston packing 22 prevents fluid from above from passingdownwardly into the cylinder space 32 below the large piston. The space32 between the lower end of the large piston and the shoulder containsno liquid at all, but only air at approximately atmospheric pressure,trapped in the space upon assembly of the device prior to its loweringin the bore hole.

A helical spring 33 is disposed in the cylinder I0 around the smallerpiston portion 21 with its lower end Vengaging the upper surface of theshoulder 29, which functions as a spring seat, and its other endengaging the underside of the large piston 2|. This spring is incompression, and tends to shift the large piston 2|, small pistonportion 21 and valve stem 20 in an upward direction to engage the valvehead I9 with its seat I8 and close the passage 34 through the valvebody, thus preventing upward flow of uid within piston or piston rodportion 21.

the tubing C through the device. Flow around the valve body and devicein an upward direction is prevented by the sealing action of the packingI4 against the Wall of the tubing.

The fluid under pressure in the tubing can act on the upper pressureactuatable surface of the large piston 2|, having an area S, by passingthrough the central passage 35 in the cylinder head Il. The total forceexerted on the large piston by the pressure acting over its area S tendsto shift the piston 2I and the small piston portion 21 and valve stem20, a; downward direction, to hold the valve head I9 from its seat I8,or in open position. The total force acting in an upward direction andtending to move the valve head I9 to closed position is the forceexerted by the coil spring 33 against the upper piston 2| plus thepressure of the fluid in the tubing acting across the pressureactuatable surface having an effective area 5, of the small So long asthe tubing pressure is high enough to furnish a total hydraulic forceacting downwardly on the large piston 2| greater than the sum of thehydraulic force acting upwardly on the small piston portion 21 plus theupward force exerted by the spring 33, the valve head I9 will be heldfrom its seat I8, or in open position. When thepressure in the tubingdiminishes sufficiently, the total downward force acting on the largepiston 2| will be less than the sum ofthe upward force exerted by thespring 33 and the hydraulic force acting upwardly on the small pistonportion 21, causing the spring 33 to movev the valve head I9 to closedposition against its seat |8.

The pressure at which the valve will close can be predetermined by therelationship between the area S across the large piston 2| and the areas of the small piston portion 21, and also by the degree of compressionor force of the spring! 33. For example, letitbe assumed' that the flowthrough the tubing is being substantially restricted by a flow bean (notshown) at the surface of the well bore to build up a4 back pressure inthe tubing string both above and below the well device of 600 p. s. i.Let it further be assumed that it is desiredI to yhave, the valve closevupon drop in the tubing pressure to approximately 300 p. s. i., whichwill occur either asa. result of opening the iiow bean to agreaterextent or through disruption of the surface well connections. Ifthe area of the large piston is assumed to be 3A, sq. in., and the areaof theY small piston Tag sq. in., the upward force F` tov be exerted bythe coil spring when the valve 1s open can be predetermined from thefollowing equation: t

PXSIF-l-PXS where: Pzdesired unit closing pressure in p. s. 1.2300Szarea of large piston in sq. in.:% szarea of small piston in sq. inzlFzforce exerted by coil spring in lbs.

SOOXSzE-i-SOOXg F:168'.75 lbs., or approximately l'10.lbs-.

In other words, under the assumed conditions,

if the spring 33 has acompressive force with the.

valve open of about 17o-lbs., the valve will close upon drop in thetubing pressure immediately below 300 p. s. i. A pressure of 600 p. s.i., or any pressure at or above 300 p. s. i.will hold the valve, open.

The valve device A canbe made upand runl in a,

well bore with the tubing string C, if desired, with the cylinder lil orvalve body l2 suitably secured to the tubing, or, as shown in thedrawings, it can be run in and anchored to tubing already positioned inthe well bore. In this latter instance, an anchoring device is attachedto the cylindrical body lil to form an upward extension thereof andincludes a tubular mandrel 36 having its lower member 36a threaded intothe adapter or cylinder head Il and its upper member 36h threaded intothe lower member. The upper mandrel member 35D is provided at its upperend with an enlarged head 3'! slidably receiving a retrieving sleeve 38,on the lower end of which is threaded a latch carrier 39 having aninturned shoulder 4l! forming a seat for a helical spring 4| whose upperend engages the mandrel head 3l. A plurality of circumferentially spacedspring-like latches 42 are formed integrally with and depend from thelatch carrier 39, each latch having a rigid head 43 at its lower endprovided with an integral dog or slip 44 of such length as to be able tolit within a coupling space 45 formed between adjacent sections 46, 4lof tubing. The head 43 also has a foot portion 48 depending from the dog44, and Aan inwardly projecting lug 49 above the foot. A latch lock orholder 50 is formed on the upper end of the lower mandrel member 36a,and has a shoulder 5l adapted to engage the lower end of the lug 49, andalso an outer surface 52 engageable with the inner surface 53 on eachfoot 48 to prevent inadvertent inward movement of the latch 42 after itsoutward expansion into the tubing coupling space 45.

When the tool is run downwardly through the tubing, the latches 42 areprevented from moving outwardly, due to their inherent spring action, bya cup-shaped retainer 54 engaging the outer surface of each latch foot48. This retainer is slidable longitudinally on the lower mandrel member35a in moving to and from latch retaining position. Circumferentiallyspaced leaf springs 55 are secured to the latch retainer by screws 56 orthe like, and frictionally engage the tubing C, tending to resistmovement of the latch retainer 54 therewithin.

A running-in tool D is employed for lowering and setting the tool in theproduction tubing already installed in the well bore. This tool consistsof an upper body 51 received within the retrieving sleeve 38 and havinga depending pilot 58 provided with an external circumferential groove 59in which is positioned a split coupling ring which inherently tends toexpand in an outward direction. A companion internal groove 6I is formedin the mandrel head 31 for reception of the split ring 56 to couple therunningin tool to the mandrel 36. A stinger or valve opening rod 52 issecured to the pilot 58, as by a set screw 63, and extends downwardlythrough the central passage in the mandrel and cylinder head intoengagement with the upper end of the large piston 2l. The valve openingrod 62 is of such length as to move the piston 2i downwardly against theaction of the spring 33 when the coupling ring 65 is in the internalgroove 6l to hold the valve in open position while the valve device isbeing run downwardly through the tubing C. f

The parts are all arranged as disclosed in Fig. 2, with the running-intool D in proper position within the mandrel 3B and cylinder I0. It isto be noted that the mandrel 3B has been moved down with respect to theretrieving sleeve 38 and latches 42 to dispose the latch lock 50 belowthe heads 43, which allows the latter to be forced inwardly and held inretracted position by the retainer sleeve 54 positioned over the footportions 48 of the latches. The setting spring 4l has been compressedand is held in such compressed state by engagement of the foot portions48 of the latches with the tapered portion 50a of the mandrel lock 50.

The running-in tool D is secured to a suitable wireline or tubing (notshown) for lowering the entire apparatus through the production tubingC. The body 5l has sufficient weight, which may be supplemented, ifrequired, by a sinker bar (not shown) attached to its upper end, toforce the apparatus down through the production tubing. This downwardmovement is not re-` tarded by the iluid in the tubing, since thestinger 62 holds the valve head I9 open'and allows fluid to by-pass thedevice by owing upwardly through the valve body I2 and ports I3; Sincethe friction springs 55 tend to resist movement of the latch retainer 54downwardly through the tubing, it remains in position over the footportions 48 of the heads 43 to hold their dogs orl slips 44 in retractedposition.

When the approximate depth at which the apparatus is to be anchored inthe well tubing is reached, the wire line is moved upwardly causing theentire apparatus to be elevated, with the exception of the latchretainer 54, whose upward movement is prevented by the friction springs55. Such upward movement releases the latch retainer from the footportions 48 of the latches 42 and allows them to expand outwardly undertheir inherent spring action against the wall of the tubing. Thisoutward expanding action may be assisted by the force of the compressedsetting spring 4l tending to move the lock 5B upwardly with respect tothe latches to shift its conical expander portion 55d upwardly againstand along the companion inclined surfaces 48a at the inner lower ends ofthe foot portions of the dogs or slips.

The entire apparatus is elevated until the next higher coupling space 45formed by a coupling 64 connecting adjacent sections 45, 4l of tubingtogether is reached, whereupon the dogs 44 on the latches can inherentlyexpandoutwardly into this space 45, the setting spring elevating theupper mandrel member 36h and attached lower mandrel member 36a toposition the latch lock or holder 50 behind the latches, as shown inFig. 3, in which the lock shoulder 5| engages the lugs 49 and theperiphery 52 of the lock engages the inner surfaces 53 of the footportions 4S of the latches. When in this position, the apparatus cannotmove upwardly, except to a very slight extent as limited by the couplingspace, since the latches 42 are prevented from moving inwardly out ofthe coupling space 45 by engagement of the heads 43 with the p-eriphery52 of the latch holder 50. A continuation of the upward strain on thewire line or tubing attached to the running-in tool D causes the splitcoupling ring 6D to bear against the tapered upper surface 65 of theinternal groove 6I, which will shift it inwardly to release therunning-in tool D from the mandrel head 31, permitting withdrawal of therunning-in tool to the surface of the well bore, and also withdrawingits valve opening rod 62 from the mandrel 36 and cylinder l0. While thisupward force is being exerted on the running-in tool to release it fromthe mandrel, the upwardly and inwardly inclined 7. surfaces B6 on thelatch heads 43 engage the4 endV 41a of the upper tubing section 41, butAthe latch holder 50 still prevents the dogs 44 from-v moving inwardlyand holds the apparatus locked to the production tubing C against upwardmovement. Downward movement is prevented by engagement of the dogs 44with the end 46a of the; lower tubing section 46.

If the valve head I9 has engaged its seat; I8v upon withdrawal of therunning-in tool D from the apparatus, such head can be reopened simplyby applying pressure from the surface of the well bore to the fluid inthe production tubing C. This pressure acts on the large piston 2I toshift the piston rodV 21 and valve stem 20 downwardly and move the valvehead I9 from its seatv I8'.l Discontinuation of this externally appliedpressure will not cause the valve to close, because 'the pressure of the`well vuid in the tubing is then capable of acting, through the openvalve, in a downward direction on the large piston 2I, as well asupwardly on the small piston portion 21. With the valve in open positionthis well fluid flows upwardly around the valve head I9, through theannular space 34 between the valve body I2 and valve stem 20, through`the ports I3, and upwardly through the annulus 61 between the cylinder Iand tubing C to the control mechanism at the surface of the well bore,where the ow is suitably beaned or throttled to provide theA necessarynormal back pressure in the tubing string. The well pressure is actingupwardly on the packing cup I4 but cannot pass therearound because ofits sealing engagement with the wall of the production tubing, and thispressure is also incapable of forcing the entire apparatus in an upwarddirection because of the engagement of the latches 42 with the tubingend 41a of the coupling space 45. As aforestated, the latches 42 cannotbe moved inwardly out of this space because of the locking action of thelatch holder 50 on the mandrel 35. When the tubing pressure drops belowa predetermined value, the valve automatically closes because of theaction of the helical spring 33, as described above. Such actionnormally takes place either through opening the flow valve at thesurface ofy the well boreY to decrease the Vfluid pressure in thetubing, or through inadvertent disruption of the surface connections,which can occur as aV resultV of hurricane or other natural hazards, oras a result of explosive forces.

The device may be retrieved from the well bore whenever desired byrunning a retrieving tool E into theA production tubing C on the end ofa wire line or other suitable string (see Figure 4). The retrieving toolincludes a body 68 adapted to be received within the retrieving sleeve38, which is provided with a pilot 69 for reception within the mandrelhead 58. This pilot also carries a depending stinger or valve openingrod secured to it in suitable fashion,l as by a set screw 1I, whichextends through the mandrel 3B and engages the; large piston 2l to forceit downwardly against the action of the spring 33and move the valve headI9 fromits seat I8- The tool body 68 is provided with a slip receivinggroove 12 whose base portion forms a slip vex-V pander 13 inclined in adownward and outward direction. A slip 14 is received within this groove12 and is held therein by a retainer screw 15 extending through anelongated slot 16 in ther base portion of the slip and threaded into thebody 68 of the retrieving tool.

ventzitslossfromthe; body, but still permits slid-- ingaction of; theslip on the expander portion 13 ofthe body. This; slip- 14 is providedwith external VWichers 18, preferably formed as a portion ofv a helicalthread, which are adapted to engage companion internal ratchet threads19' and causes its wickers'18 to engage the ratchet,

teeth 1.9; In effect, the slip and ratchet teeth onl the retrievingsleeve form a one-way clutch, which allows downward movement of the body68 andy attached stinger 10 with respect to the retrieving sleevel 38,but prevents their relative upward movement.

TheV retrieving tool Eis lowered through the production tubing C untilit enters the mandrel 35i and retrieving sleeve 38. Engagement of thedogs 44 with the end of the lower tubing section 4E prevents downwardmovement of the latches 42. and retrieving sleeve 3B, and allows theweight of. the body 58 to be imposed on the stinger 10 to open the valveagainst the force of the spring 33 and production tubing pressure. Thisweight also forces the mandrel 36down to recompress the setting spring4I and shift the latch holder 56 downwardly from the latch dogs. Thelatch holder 5t is held in this lower position and the valve maintainedopen by the clutching engagement of the slip 14 with the retrievingsleeve 38 and engagement of the body B8. with the mandrel head 3f1.Upward movement of the wire line then elevatesv the entire mechanismthrough the production tubing, the inclined surfaces 66 of the latchheads 43 engaging thelower end 41a of each tubing section 41 to beforced inwardly free of the coupling spaces 45v during upward'travel ofthe mechanism. These latches 42 ride along the walls ofthetubing'sections until the entire device is withdrawn from the tubing atthe surface of the well bore. The retrieving tool E can then bewithdrawn from the mandrel by unscrewing the body andits slipy 14 fromthe ratchet threads 19 in the retrievingsleeve 38.

For the purposerof' facilitating opening of the valve; the valve head I9may be formed in sections, being provided with an auxiliary orequalizing valve headV extendingY downwardly from a rod extension BIsecuredto the valve stem 20 by a coupling 82. The equalizing valve head|83 is adapted to engage an auxiliary valve seat 83 at the lower endofthe main valve head I9. When the valves are closed, the auxiliary valve:head 80 engages its companion seat 83 on the main valve head I9 and thelatter engages its seat I8 on the` clamp nut I1. When the valve is to beopened, the iirst portion of the downward movement of the valve stem 20disengages they auxiliary valve head Si! from its seat 83 and permitsthe pressureY to equalize onboth sides of the main valve head Itisapparent from the foregoing description.

Continued downward movementy that the valve is open both while being runinto and removed from the production tubing, and, therefore, can readilybe moved through the tubing since the fluid therein is lay-passedthrough the open valve and remains substantially undisturbed in thetubing.

is an alternative method of keeping the valve in open position afterinstallation of the device in the tubing, fluid pressure may be suppliedfrom the surface of the well bore, being conducted into the up-per endof the cylinder iii through a separate string of tubing 85 extendingdownwardly from the top of the bore hole and threaded into theretrieving sleeve 38. The pressure will be transmitted through the uidin this tubing and through the mandrel 36 into the head end of thecylinder IG, where it will act downwardly-on the large piston 2l toshift the valve head lfrom its seat I8. The well flow can then takeplace as before through the open valve, through the annular space 3sbetween the valve body I2 and stern 20, and through the ports I3 forupward passage around the tool and the annular space between the innertubing string 35 and production tubing C to the surface of the wellbore. With this arrangement, the pressure acting down on the largepiston 2| is independent of the production tubing pressure, and thevalve can be opened or closed at -will 'simply by controlling thepressure of the iliiid within the inner tubing string 85.

It is detrimental to some wells for its ilow to n be arrestedcompletely. For wellsof this type, the valve head I9 can be so arrangedas not to close completely when the well pressure decreases below apredetermined degree. A suitable 'port 86 may be formed through theclamp ring i2' to allow some fluid to continue to by-pass the valve headi9 and now through the ports i3 upwardly through the tubing to thesurface of the well bore; or the valve stem 2i) may be of such length asto leave the valve head I9 slightly spaced from its seat I8 when thelarge piston 2| is in its uppermost position. By materially decreasingthe now under the Vlast-mer'iticihed conditions, the well can still becontrolled at the surface of the well bore, even upon disruption of thesurface control valves by natural or man made forces.

A modified form of the invention is disclosed in Figs. 6 and 7.Essentially, lthe device illustrated in these iigures is substantiallythe same as the other device insofar as the anchoring mechanism B isconcerned It also embodies the principle of the differential areas andpredetermined spring tension or compression for controlling operation ofthe Valve. The main di'erence resides in the provision of a differenttype of seals for the large and small pistons 2 l 21, and also in theprovision of an arrangement for readily adjusting the force of thespring 33.

As shown in the drawings, a cup-shaped eX- tensible piston packing '8lhas its upper end 33 clamped betweenv the cylinder l0 and cylinder head,and its lower base portion 89 resting upon the head of the large piston2 la. Y A suitable filler cup or thimble en can be inserted in the cup-Shaped packing for engagement by the valve opening rods 62, 'is of therunning-in and retrieving tools D, E', and thus prevent potential damageto the cup-shaped packing. The piston rod or small piston 27a is alsoprovided with an extensible piston or rod packing 9| whose upper end 92is clamped to the cylinder lila, by a lower clamp ring 93 engaged by theupper end of a spring housing 94 threaded into the lower end of thecylinder Ia.. The lower` Gilde 95 Of the 10 1 small piston packing 5I isclamped to the small piston 2id by a clamp nut St threaded on thislatter member.

The valve body I2 is threaded into the lower end of the spring housing94 and forms a seat for the bottoni end of the spring 33, Whose upperend engages an adjustingnut El? threaded on the valve stern 2te, whichextends upwardly into the spring housing with its upper end engaging thelower end of the small piston`2ld. A lock nut 98 is threaded on theupperend of the valve stem 26a to hold the nut 97 in any position ofadjustment.

As described in connection with the other embodiment shownin thedrawings, the pressure of the iiuid in the production tubing actsYupwardly over the eflective area s of the small piston 21a to urge thevalve head I9 to closed position, and this force is supplemented by theaction of the spring 33, whose compression is predetermined byappropriately threading the adjusting nut el on the threaded valve stem20a. The pressure of the fluid in the production tubing is also actingdownwardly on the large piston 2 la f over its effective area 5, tendingto move the closes under the action of the spring 33.

The inventor claims: l. A well flow control device including a body 'Kadapted to be disposed within a now line and having a passage throughwhich well fluidmay iiow, means for preventingv fluid flowlongitudinally along the exterior of said body between said body and theflow line surrounding said body, a valve movable' by said well iluidtoward a position closing said passage, means having a fluid pressureactuatable surface responsive to the action of said well iiuid underpressure on the outlet side of said valve for urging said valve to openposition to permit flow of fluid through said passage, means havingafluid pressure actuatable surface of less area than saidiirst-mentioned surface and responsive to the action of said well uidunder pressure for urging said valve toward closed position, and meanssupplementing the k'force of the fluid pressure on said surface of lessvalve means coacting withsaid body and movable v to positions regulatingthe how of fiuid through said passage, means for urging said valve meansin an upward direction toward closed position, said valve means havingan upper nuid pressure actuatable surface responsive to the action loffluid under pressure in-said tubing above said device on the outlet sideof said valve means rfor urging said valve means in a downward directionto open position to permit flow of weil fluid'upwardly through saidpassage, said valve means also having a fluid pressure actuatable'surface of less area than said rst-mentioned surface and responsive tothe action orwell fluid under` pressure in said tubing from below saiddevice for urging said valve means upwardly toward closed position, saidareas and urging means being proportioned and related to each other asto cause 1 l said urging means to shift said valve means 'to- Vwardclosed position upon decrease in tubing pressure above the device fromnormal to a predetermined value.

3. A Well flow control device including a body adapted to be positionedwithin production tubing and having a passage `through which well iiuidmay flow upwardly through the tubing, means for preventing fluid flowbetween said body and the production tubing, a valve coacting with saidbody andmovable to positions regulating the flow Vof fluid through saidpassage, said valve being movable by the pressure of said well fluidtoward closed position, `means for urging said valve in an upwarddirection Atoward closed position, and `fluid operated means responsiveto fluid pressure in the production tubing above said device on theoutlet side of said valve for urging said valve downwardly toward openposition to permit upward ow of fluid through said passage.

4. A well flow control device including a body adapted to b e positionedwithin production tubing, means for preventing flow of fluid betweensaid body and the production tubing, said body having a passage throughwhich Well fluid may by-pass upwardly around said flow preventing meansfor upward passage between said body and tubing, a valve coacting withsaid body and movable to positions regulating theow of well iiuidthrough said passage, means for urging said valve in an upward directiontoward closed position, and fluid operated means responsive to thepressure ofiluid Von the outlet side of said valve and above said owpreventing means for urging said valvedownwardly toward open position topermit upward flow of fluid through vsaid passage.

5. A wellv flow control device including production tubing, a bodypositioned within said production tubing and having a passage throughwhich well iiuid may flow upwardly through the tubing, means for`preventing iuid flow between said body and the production tubing, avalve coacting with said body and 'movable to positions regulating theow of fluid through said passage, means for urging said valve in anupward direction toward closed position, a cylinder secured to said bodyand spaced laterally from said production tubing, means for feedingfluid into said cylinder, and piston means in said cylinder acted on bythe iluid fed into the cylinder and coacting with said valve for urgingsaid valve in a downward direction toward open position to 'permitYupward ow of fiuid through said passage and upwardly throughsaidproduction tubing around said cylinder.

6. A well ilow control device including a body adapted to be positionedwithin production tubing and having a passage through which well fluidmay flow, means for preventing fluid flow longitudinally along theexterior of said body between saicl body and the production tubing, avalve coacting with said'fbody and vmovable to positions regulating theflow of iiuid through said passage, means for urging said valve towardclosedY position, a cylinder secured to said body and having an inletfor the entry of well ,iluid on the outlet side of said valve, pistonmeans in said cylinder coacting with said valve for urging said valvetoward open position `to permit flow of fluid through said passage, saidpiston means having a larger fluid pressure actuatable surface subjectto the pressure of the well fluidentering said cylinder through saidinlet to urge vsaid valve toward open position, andpiston means coactingwithY said valve and having a smaller iiuid pres- .75 a'valVe it/.aldplgfd Dition upon decrease Y sure actuatable surface subject tosubstantially.

the same vpressure as the well uid in said passage for urging said valvetoward closed position, said areas of said surfaces and said urgingmeans being proportioned with respect to each other :as to cause saidurging means to shift said valve toward closed position upon decrease inwell pressure from normal to a predetermined lower value.

7. A well flow control device vincluding a body adapted to be positionedwithin production tubing and having a passage therethrough through whichfluid `may flow upwardly through the tubing, a, valve coacting with saidbody and movable to Apositions regulating the iiow of fluid through saidpassage, ra spring urging said 4valve in an upward direction towardclosed pos'ition,` acylinder secured to said body andliaving an inletfor Vthe entry of -uid .from said production tubing onthe outlet 'sideof :said valvel means .for preventing fluid flow longitudinal-ly alongthe exterior of said body between said ,body .and production tubing, an`upper piston in said cylinder lexposed to the action of well uid insaid cylinder and inlet, a lower piston exposed to the action of wellfluid yfrom below said cylinder, said pistonsV coacti-ng with said valveso that said upper piston urges said valve toward open position topermit ilow of fluid through -said passage and said lower piston tendsto counteract the valve opening action of said upper piston, said upperpiston having a fiuid pressure actuatable surface .of larger area thanthe fiuid pressure actuatable surface of ,said

lower piston, and said .areas Aof said surfaces and force of ysaid4spring being .proportioned and related to each other as to cause saidupper piston Vto hold said valve in open position under normal welllpressure flowconditions and said spring -to shift said val-ve towardclosed position upon decrease in Well pressure-from normal to apredetermined lower value.

8. A well flow control device including production tubing, Aa bodywithin said production tubing and having a `cylinder extending upwardlytherefrom and spaced inwardly from said production tubing, means forpreventing flow of fluid between said body and production tubing, saidbody having a lpassage through which uid vmay bypass upwardly aroundsaid now `preventing means for upward passage through the space betweensaid tubing vand cylinder, a valve coacting with said body and ,movableto positions regulating the ilowgof duid through saidpassage,.a springurging' tends to counteract the valve opening action ofV said upperpiston, said lupper piston having a fluid pressure actuatable surface oflarger area than the fluid-pressure actuatable surface of said lowerpiston, and said areas of said surfaces and force of said spring beingso proportioned with respect Vto one another that -the pressure of thewell fluid fiowing through the device under norvmal well iow conditionswill act on said pistons to counteract the force Of. Said spring to hold,the valve 1n Open position, said spring shifting -13 in the Wellpressure from normal to a predetermined lower value. l

9. A well flow control device adapted to be moved longitudinally througha tubularstring, including a body having a passage through whichfluid-may flow through the tubular string, a valve coacting with saidbody and movable to positions regulating the flow of fluid through saidpassage, a spring urging said valve toward closed position, cylindermeans secured to said body and having a fluid inlet, a piston in said'cylinder means acted on by fluid fed into said cylinder means throughsaid inlet and coacting with said valve for urging said valve towardopen position to permit ilow of fluid through said pas- 2* sage, and atool releasably connected to said cylinder means for moving, said devicethrough said tubular string comprising a rod engageable with said pistonfor holding said valve open.

10. A well flow control device adapted to be lowered through a tubularstring, including a body having a passage through which fluid may flowthrough the tubular string, a valve coacting with said body and movableto positions regulating the flow of fluid through said passage, a springurging said valve toward closed position, a cylinder secured to saidbody and having a fluid inlet, a piston in said cylinder acted on byfluid fed into said cylinder through said inlet and coacting with saidvalve for urging it toward open position to permit flow of fluid throughsaid passage, means secured to said cylinder for anchoring said body andcylinder to said tubular string, a tool releasably conected to saidanchoring means for lowering said device through said tubular stringcomprising a rod engageable with said piston for holding said valveopen, and means for holding said anchoring means in retracted positionwhile said device is being 10W- ered through said tubular string.

1l. A well flow control device adapted to be secured within a flow lineincluding a body havv between said body and the flow line, a valve mov-.3;

able to positions regulating the flow of fluid under pressure throughsaid passage, means having a fluid pressure actuatable surfaceresponsive to the action of fluid under pressure above said passage onthe outlet side of said valve and within said flow line for urging saidvalve to open position to permit flow of fluid through said passage,means having a fluid pressure actuatable surface of less area than saidfirst-mentioned surface and responsive to the action of fluid underpressure within said flow line for urging said valve toward closedposition, means supplementing the force of the fluid pressure on saidsurface of less area for urging said valve toward closed position, saidfluid pressure actuatable surfaces and said supplementing means beingproportioned and related to one another as to hold said valve in fullyopened position until the fluid pressure through said passage decreasessubstantially below normal to a predetermined value.

l2. A well flow control device including a body having a passage throughwhich well fluid may fioW, a valve movable to positions regulating theflow of fluid through said passage, means having a fluid pressureactuatable surface and adapted' to urge said valve to open position topermit ilow of fluid through said passage, means on the outlet side ofsaid valve for imposing static pressure only on said fluid pressureactuatable surlface of less area for urging face of said urging meansvto urge said valve to open position, means provided with a fluidpressure actuatable surface of less area than said first-mentionedsurface and responsive to the action of fluid under pressure for urgingsaid valve toward closed position, and means supplementing theV force ofthe fluid pressure on said sursaid valve toward closed position.` I

13; A well flow control device including a body having a passage throughwhich well fluid may flow, a4 valve coacting with said body and movableto positions regulating the flow of fluid through said passage, meansfor urging said valve toward closed position, a cylinder. secured tosaid body and `having an inlet for the entry of Well fluid which isspaced longitudinally from'said passage, piston means in said cylindercoacting with said valve for urging it toward open position to permit'flow of well fluid through said passage, said piston means comprisinglarge and small pistons operatively associated with one another andmovable within said cylinder, said large and small pistons being inleakproof relation with respect to said cylinder providing a connedcylinder space therebetween into which said well fluid cannot enter,said large piston being subject tothe pressure of the well fluidentering said cylinder through said inlet to urge said valve toward openposition and said smaller piston being subject to the pressure of thewell fluid above said valve for urging said valve toward-closedposition, the fluid pressure actuatable areas of said large and smallpistons and said urging means being so proportioned with respect to eachother as to cause said urging leans to shift said valve toward closedYposition upon decrease in well pressure from normal to a predeterminedlower value.

14. A well flow control device including a body having a passage throughwhich well fluid may flow, a valve coacting With said body to regulateflow of fluid through said passage, means for urging said valve towardclosed position, a cylinder secured to said body and having an inlet onthe outlet side ofl said valve which is spaced longitudinally from saidpassage, first piston means in said cylinder coacting with said valvefor urging said Valve toward open position to permit flow of fluidthrough said passage, said rst piston means having a fluid pressureactuatable surface subject to lluid pressure entering said cylinderthrough said inlet to urge said valve toward open position,V

means preventing the well fluid from acting upon said iirst piston meansto urge said ilrst piston means in the opposite direction such as wouldcause said valve to move toward closed position, and second piston meanscoacting with said valve and having a smaller fluid pressure actuatablesurface than said iirst piston means subject to substantially the samepressure as the Well fluid in said passage for enabling said valve tomove toward closed position. l

15. A well flow control device adapted to be lowered through a tubularstring, including a body having a passage through which fluid may flowthrough the tubular string, valve means secured to and coacting withsaid body and movable to positions regulating the flow of fluid throughsaid passage, a mandrel secured to said valve means, means on saidmandrel for anchoring said mandrel to said tubular string, means on saidmandrel for retaining said anchoring means in retracted position whilethe device is being lowered through the tubular string, said retainingvmeans being frictionally .engageable with said Num'loei' .Name Datetubular string, 'a Ytool relea'saloly connectedtofsai'd 1,087,399 PhelpsFeb. .17, 1914 4mandrel for lowering said `olevice through ssaid1,283,061 .Bridgham Oct. 29, 1918 tubular string, Ysaid retaining meansbeing mov- 22,196,535 vOtis Apr. 9, 1940 able to a position wthrespectto'sad vanchoring f5 12,238,124 Mathieson Apr..15, 1941 means releasingsaid anchoringmeans upon up- `21,251,244 Stanley Ju1y.v29, 1941 wardmovement of said tool and mandrel to per- 2,268,227 Rose Dec. 30, 1941mit expansion of said anchoring means toward 2,304,404 VFlanagan Dec. 8,1942 engagement with said tubular string. 2,375,810 Nelson AMay 15,1945REUBEN C. BAKER. '10 2,428,150 Field Sept. 30,1947 42,508,399 KendrickMay V23, 1950 References Cited in the file rof this patent UNITED STATESPATENTS 1,001,324 'Thompson Aug. 22, t191

